The present invention relates to position adjuster apparatus and, in particular, to apparatus for adjusting an article or system such as a lens mount or mirror mount or optical beam sensor in x or x, y coordinates.
In general, the present invention is applicable to items or systems which require or would benefit from precise, convenient position adjustment along one or more co-planar directions such as, for example, the above-mentioned sensors used in optical systems. In one specific aspect, the present invention relates to an adjustable mount or stage of the type which has an aperture or optical window for transmitting an optical beam, and which mounts an electromagnetic sensor in the aperture to detect the beam position. Quite obviously, in such adjustment stages it is highly desirable to provide a large area beam transmission aperture or hole.
An efficient ring-type precision adjustable stage is disclosed in copending commonly assigned Cutburth and Silva U.S. patent application Ser. No. 911,845, filed Sept. 26, 1986, entitled PRECISION ADJUSTABLE STAGE. Cutburth and Silva disclose a stage center block which is mounted on each of two opposite sides by a pair of spaced ball bearing tracks which provide stability as well as simplicity. The use of the spaced ball bearing mounting pairs in conjunction with a manual adjustment screw eliminates extraneous stabilization components which may be required, for example, in micrometer-type, differential motion systems, and permits maximization of the area of the laser transmission hole. However, to our knowledge, previously there has not been available a precision adjustable motorized stage which is compact, yet provides a large area beam transmission hole.